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Öğe Antiepileptic drug-induced osteopenia in ambulatory epileptic children receiving a standard vitamin D3 supplement(Freund Publishing House Ltd, 2005) Tekgul H.; Dizdarer G.; Demir N.; Ozturk C.; Tutuncuoglu S.Dual energy X-ray absorptiometry (DEXA) is a non-invasive, rapid, accurate and highly reproducible method for the assessment of antiepileptic drug (AED)-induced osteopenia in epileptic children. In this study, we investigated bone mineral density (BMD) using DEXA in 56 epileptic children receiving long-term AED treatment for at least 2 years. All children received AED monotherapy or polytherapy plus a standard vitamin D3 supplement (400 U/day). BMD measurements were made from lumbar spine (L2-L4) regions. Age- and sex-specific BMD SD scores were calculated for each child. Osteopenia was defined as SD scores less than -1.5. There was no significant difference in mean BMD values between epileptic children receiving monotherapy or polytherapy. The results were also compared to the age- and sex-specific BMD SD scores obtained from healthy Turkish children. Only three patients (5%) receiving AED therapy had a BMD SD score less than -1.5. This rate is relatively lower than the rates of previous studies conducted on ambulatory children on long-term AED treatment without vitamin D3 supplementation. © Freund Publishing House Ltd., London.Öğe Assessing the Impact of the Türkiye February 2023 Earthquakes on Cultural Heritage Sites: A Multi-Disciplinary Approach Utilizing ARIA Maps and Social Media Collaboration(International Society for Photogrammetry and Remote Sensing, 2024) Demir N.; Çilingiroğlu Ç.The earthquakes that occurred in our country on February 6, 2023, significantly damaged and destroyed cultural and historical assets. The Habib-i Nejjar Mosque in Antakya and other important historical sites suffered significant damage. This study provides a comprehensive account of the post-earthquake efforts carried out by volunteers from various disciplines, including archaeology, cartography, space sciences, and architecture, using social media platforms. The volunteers created an extensive database for cultural and archaeological sites in all 11 provinces that were declared disaster zones. This database made it easier to conduct a thorough evaluation of the damage. The database was augmented with surface displacement data, enabling an analysis of damage levels with the exactitude facilitated by the gathered information. The utilization of the Advanced Rapid Imaging and Analysis (ARIA) maps was pivotal in this study. The maps, created through partnerships between NASA and different space agencies, offer intricate satellite imagery and analysis of surface displacement. This is essential for evaluating the effects of earthquakes on cultural heritage sites. The utilization of ARIA maps in this study facilitated an accurate assessment of the seismic impact on cultural and historical resources. Additionally, Sentinel 1 images are used to generate displacement maps with the use of the LICSAR tool and the SBAS method. The study examined the state of about 1500 cultural heritage sites in 11 provinces in the aftermath of the earthquake. The report incorporated data from media coverage and input from relevant parties present at the scene, providing a thorough assessment of the situation following the disaster. For instance, the research revealed substantial shifts at prominent locations, like the UNESCO World Heritage site of Arslantepe in Malatya. This site experienced a displacement of over one meter towards the south and 75 cm towards the west, along with a subsidence of approximately 10 cm in the surrounding area. Furthermore, the study presented a visual representation that depicted the quantity of impaired cultural heritage sites in every province, providing a comprehensive evaluation of the impacted cultural and archaeological resources. This comprehensive strategy not only emphasized the magnitude of harm to cultural heritage but also emphasized the significance of interdisciplinary cooperation in disaster response and heritage preservation. © Author(s) 2024.Öğe A confusing coincidence: Neonatal hypoglycemic seizures and hyperekplexia(Hindawi Limited, 2014) Demir N.; Dogan M.; Ylmaz S.; Peker E.; Bulan K.; Tuncer O.Hyperekplexia is a rare, nonepileptic, genetic, or sporadic neurologic disorder characterized by startle responses to acoustic, optic, or tactile stimuli. Genetic defects in glycine receptors as well as encephalitis, tumors, inflammation, and disgenesis are among the etiologic causes of the disease. The main problem in hyperekplexia is the incomplete development of inhibitory mechanisms or exaggerated stimulation of excitatory mediators. Hyperekplexia is often confused with epileptic seizures. Here we present a case with hypoglycemic convulsions coexisting with hyperekplexia, causing diagnostic difficulty. © 2014 Nihat Demir et al.Öğe Degradation of a textile dye, Rhodamine 6G (Rh6G), by heterogeneous sonophotoFenton process in the presence of Fe-containing TiO2 catalysts(Springer Verlag, 2015) Demir N.; Gündüz G.; Dükkancı M.In this study, degradation of Rhodamine 6G (Rh6G) was investigated with ultrasound-assisted heterogeneous photoFenton process by iron-containing TiO2 catalysts. The catalysts were prepared by incipient wetness impregnation method and characterized by XRD, SEM, FT-IR, nitrogen adsorption, and ICP-AES measurements. Almost complete color removal (99.9 %) was achieved after a reaction time of 90 min while chemical oxygen demand (COD) could be removed by 24 % only with the 1 wt% iron-containing TiO2 catalyst. Initial color removal after 15 min of reaction and total COD abatement after 90 min of reaction decreased with increasing calcination temperature of the catalyst from 573 to 973 K. This indicated that the catalytic activity of the catalyst depend on the percentage of anatase phase in the TiO2, which was decreased with increasing calcination temperature. © 2014, Springer-Verlag Berlin Heidelberg.Öğe Effect of angiotensin II type 1 receptor blocker on osteoporotic rat femurs(Elsevier B.V., 2012) Donmez B.O.; Ozdemir S.; Sarikanat M.; Yaras N.; Koc P.; Demir N.; Karayalcin B.; Oguz N.Background: Osteoblasts and osteoclasts are known to express Ang II type I (AT1) receptor in cell cultures, suggesting the existence of local renin-angiotensin system (RAS) in bone. This study was designed to investigate the effects of losartan as AT1 receptor blocker on ovariectomized rats' femur. Methods: Losartan (5 mg/kg/day) was administered via oral gavage for 8 weeks. Bone mineral density (BMD) was measured using dual energy X-ray absorptiometry, while tensile and three-point bending tests were performed for evaluation of biomechanical properties of bone. The trabecular porosity was analyzed by scanning electron microscopy. Results: There was a significant decrease in BMD values of ovariectomized rats' femurs which were reversed by losartan treatment. According to tensile test results, ultimate tensile strength and strain values of losartan treated ovariectomized rats' femurs increased and decreased, respectively, when compared to that of ovariectomized animals. Losartan treatment also caused a significant recovery in flexural strength and modulus parameters regarding respective control values, which mean losartan treated ovariectomized rats' femur had more force tolerance until break than ovariectomized rats' femur. Quantitative microscopic analysis showed larger trabecular porosity in ovariectomized rats than control rat femurs and it was significantly decreased after losartan treatment. Conclusion: Blockage of AT1 receptor increased strength, mass and trabecular connections of ovariectomized rat femurs. Therefore, it is tempting to speculate that drugs, including AT1 receptor blockers, may be used for the treatment of osteoporosis or reduction of its detrimental effects in the future. Copyright © 2012 by Institute of Pharmacology Polish Academy of Sciences.Öğe Effect of seaweed suspensions on seed germination of tomato, pepper and aubergine(Asian Network for Scientific Information, 2006) Demir N.; Dural B.; Yildirim K.Three seaweed suspensions obtained from green algae Codium tomentosum Stackhouse, red algae Gracilaria gracilis (Stackhouse) Steentoft, Irvine and Farnham and brown algae Cystoseira barbata (Stackhouse) C. Agardh were tested for their effects on the seed germination of tomato, pepper and aubergine at optimum (25°C) and low temperatures (15°C). Results showed that brown and green algal suspensions increased germination significantly (p<0.05) at both temperatures in pepper and aubergine, being more prominent at low temperature than that of optimum. All suspensions were not effective in tomato seeds at both temperatures. Treated tomato seeds had slightly higher or equal values to control at optimum and low temperature. Pepper seeds treated with green seaweed had higher germination than those of others and the percentages were recorded as 52 and 68% at 15 and 25°C, respectively. Germination percentages of aubergine seeds treated with green seaweed bad 91% at low and 88% at optimum temperatures. © 2006 Asian Network for Scientific Information.Öğe Efficiency enhancement in a single emission layer yellow organic light emitting device: Contribution of CIS/ZnS quantum dot(Elsevier, 2015) Demir N.; Oner I.; Varlikli C.; Ozsoy C.; Zafer C.Electroluminescence (EL) efficiency from a single emission layer solution processed yellow emitting polymer, i.e. poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-{2,10,3}-thiadiazole)] end-capped with dimethylphenyl (ADS233YE), is firstly enhanced by the optimization of stock polymer concentrations and the coating rates, and then with the addition of copper indium disulfide/zinc sulfide (CIS/ZnS) core/shell quantum dots (QDs). Using these bare core/shell QDs as the active layer in the studied device gave no EL at all. However, yellow EL with the maximum brightness of 56834 cd/m2, maximum current efficiency of 4.7 cd/A and maximum power efficiency of 2.3 lm/W is obtained from the device structure of indium tin oxide/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)/ADS233YE:0.4 wt.% CIS/ZnS QD/Ca/Al those of which correspond to approximately 4 and 2 folds of enhancements in the brightness and luminous and power efficiency values, respectively, compared to that of the device without CIS/ZnS. © 2015 Elsevier B.V.Öğe Outcome of the Respiratory Syncytial Virus related acute lower respiratory tract infection among hospitalized newborns: A prospective multicenter study(Taylor and Francis Ltd, 2016) Alan S.; Erdeve O.; Cakir U.; Akduman H.; Zenciroglu A.; Akcakus M.; Tunc T.; Gokmen Z.; Ates C.; Atasay B.; Arsan S.; Anik A.; Turkmen M.K.; Erdogan Y.; Oygur N.; Kahvecioglu D.; Yildiz D.; Caner I.; Tekgunduz K.S.; Kurt A.; Yigit Y.; Bilgili G.; Bolat F.; Cevit O.; Ozlu F.; Satar M.; Ertugrul S.; Cakir B.; Unal S.; Iscan B.; Duman N.; Ergor S.N.; Yalaz M.; Celik I.; Celik U.; Hirfanoglu I.M.; Koc E.; Sivasli E.; Melekoglu N.A.; Kiray Bas E.; Bozkaya D.; Korkmaz A.; Ozdemir R.; Karadag A.; Ozer E.; Ilhan O.; Mutlu M.; Aslan Y.; Erener- Ercan T.; Cetinkaya M.; Sahin O.; Akin M.A.; Okumus N.; Demirel G.; Kilic A.; Turkoglu-Unal E.; Bulbul A.; Takci S.; Anuk-Ince D.; Ciftdemir N.A.; Acunas B.; Ozkan H.; Koksal N.; Okulu E.; Demir N.; Tuncer O.; Dizdar E.A.; Oguz S.; Dilmen U.Aim: To determine the incidence and outcomes of respiratory syncytial virus (RSV)-related acute lower respiratory tract infection (ALRI) including morbidity, nosocomial infection and mortality among newborn infants who were admitted to the neonatal intensive care units (NICUs).Methods: A multicenter, prospective study was conducted in newborns who were hospitalized with community acquired or nosocomial RSV infection in 44 NICUs throughout Turkey. Newborns with ALRI were screened for RSV infection by Respi-Strip®-test. Main outcome measures were the incidence of RSV-associated admissions in the NICUs and morbidity, mortality and epidemics results related to these admissions.Findings: The incidence of RSV infection was 1.24% (n: 250) and RSV infection constituted 19.6% of all ALRI hospitalizations, 226 newborns (90.4%) had community-acquired whereas 24 (9.6%) patients had nosocomial RSV infection in the NICUs. Of the 250 newborns, 171 (68.4%) were full-term infants, 183 (73.2%) had a BW >2500 g. RSV-related mortality rate was 1.2%. Four NICUs reported seven outbreaks on different months, which could be eliminated by palivizumab prophylaxis in one NICU.Conclusion: RSV-associated ALRI both in preterm and term infants accounts an important percent of hospitalizations in the season, and may threat other high-risk patients in the NICU. © 2015 Taylor & Francis.Öğe A pilot-scale unit for suspended cultivation of Gracilaria gracilis in Izmir Bay, Aegean Sea-Turkey(2006) Dural B.; Demir N.; Sunlu U.A metal frame with dimensions of 1 x 1 x 1 m for the suspended cultivation of Gracilaria gracilis (Stackhouse) Steentoft, Irvine and Farnham was settled in shallow water in Inciralti in Izmir Bay. The alga was tied by sixteen ropes just below the surface of the water (0.1-0.2 m), at mid depths (0.6-0.7 m) and near the bottom (1.1-1.2 m). The total of 16 plants were measured weekly from July 28th to October 20th 2002. Water temperature, dissolved oxygen, nitrate, nitrite, ammonia, orthophosphate and silica were also analysed. The healthy growth of algae was observed only at mid depth. The plants near to the surface died because of waves, water level fluctuations or direct sunlight. Gracilaria suspended near to bottom was lost, consumed by fish or bleached and died after two weeks. Relative growth rates varied from 8.2 to 0.96% day-1. At the end of the experiment, mean individual weight of plants reached to 9.3 g. © 2006 Asian Network for Scientific Information.Öğe Structure-Property Relationship in ?-Conjugated Bipyridine Derivatives: Effect of Acceptor and Donor Moieties on Molecular Behavior(American Chemical Society, 2019) Demir N.; Yakali G.; Karaman M.; Gokpek Y.; Denizalti S.; Bilgili H.; Can M.Here, we reported the photophysical studies, single-crystal X-ray crystallography, and density functional theory (DFT) calculations of two bipyridine derivative molecules. In addition, thermal gravimetric analysis and cyclic voltammetry studies were also performed for both compounds. According to crystallographic data, the ?-conjugated molecules have high-quality crystal structures as a result of intramolecular and intermolecular hydrogen bonds occurring through the molecules of the compound. It was determined that when the functional groups (F- and CH3O-) were introduced to the para positions, the molecules adopted slipped stacking (J-aggregate) and antiparallel cofacial stacking (H-aggregate). It was observed that these two bipyridine derivatives disclose the relationship between molecular conformation-molecular packing modes and photophysical behavior of organic solids. The results of DFT calculations supported the structural, spectroscopic, and photophysical data and confirmed the compositions of frontier molecular orbitals in both molecules. © 2019 American Chemical Society.Öğe Structure-Property Relationship in Amber Color Light-Emitting Electrochemical Cell with TFSI Counteranion: Enhancing Device Performance by Different Substituents on N^N Ligand(American Chemical Society, 2021) Demir N.; Karaman M.; Yakali G.; Tugsuz T.; Denizalti S.; Demic S.; Can M.Amber color emitting novel Ir(III) complexes were synthesized: [Ir(Meppy)2(Fpbpy)][PF6] (1bPF6), [Ir(Meppy)2(Fpbpy)][TFSI] (1bTFSI), [Ir(Meppy)2(MeObpy)][PF6] (2bPF6) and [Ir(Meppy)2(MeObpy)][TFSI] (2bTFSI), where Meppy = 2-(p-methylphenyl)-pyridine (b), Fpbpy = 4,4?-bis(4-fluorophenyl)-2,2?-bipyridine (1), and MeObpy = 4,4?-bis(4-methoxy)-2,2?-bipyridine (2). The photophysical and X-ray results showed that the complexes have aggregation-induced phosphorescent emission (AIPE) and a salt-induced polymorphism effect. The highest photoluminescence intensity was observed in complex 2bTFSI compared to other complexes in the solid state. Their theoretical absorption and phosphorescence emission transitions in acetonitrile were also investigated by using double- and triple-? basis sets with B3LYP and PBE0 hybrid functional. The best light-emitting electrochemical cell (LEC) performance was exhibited by complex 2bTFSI, and the data obtained were as follows: Luminance, current density, luminous efficiency, turn-on time, power efficiency, and external quantum efficiency were measured as 16 156 cd/m2, 554 mA/cm2, 8.49 cd/A, 17 s, 3.95 lm/W and 6.37%, respectively. The investigation of crystallographic characteristics have shown that the LEC performance of these complexes depends on cationic-anionic interaction which has a significant influence on molecular stacking of the molecules. Because, complex 2bTFSI, with weak cationic-anionic interactions, shows strong ?···?stacking interactions between the adjacent molecules, it is the best lighting application candidate among the complexes. © 2021 American Chemical Society.
